It's my understanding that there is a really great chance that 4.4 will never be released. At least according to php.internals forum...
If it's going to be finished at least with the RC1 phase, I would update DBG to support it. Otherwise, I'll do update for supporting php5 only.
Regarding the recently released 4.3.4rc1, dbg 4.3.3 should work with it.